Heart failure (HF) is defined as the inability of the heart to supply peripheral organs with sufficient blood flow. It may be characterized by a hyperadrenergic state whereby increased systemic levels of norepinephrine (NE) and increased local spillover of catecholamines occur. The condition afflicts increasingly more people each year and is a common end-stage of many cardiac diseases and conditions including myocardial infarction, pressure/volume overload, viral myocarditis, toxic cardiomyopathy, valve failure, and other abnormalities. The resultant myocardial damage, in conjunction with neurohormonal and cytokine activation, stimulates chamber remodeling which is the initial phase of heart failure. This remodeling process results in decreased overall myocardial efficiency and eventual progression to clinical HF. To date, however, no cure for the condition exists, thus early diagnosis is a key factor in its management and long-term prognosis. An imaging agent that identifies subjects in early HF would thus enable treatment and life-style improvements for patients living with the condition.
Myocardial damage may also occur following tissue insult (e.g., a myocardial infarction), whereby innervation and perfusion defects may form in a portion of the subject (i.e. a portion of the heart). In certain cases, the size of the defect areas, as detected by imaging, could be different (e.g., regional mismatch) and may be associated with an increased probability for cardiac arrhythmia as well as other conditions.
Accordingly, improved compositions, methods, systems, and apparatuses are needed for the synthesis and administration of imaging agents (e.g., for imaging the heart).